The Republicans did have to cope with many retirements, which in 2018 reached a high for Republicans going back at least as far as 1930. But Trump is wrong that the Republicans outperformed historical precedents. The losses were fairly average or worse than average.

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Indeed, if you look just at losses suffered under Republican presidents, the total for 2018 exceeds all but two midterms going back to the Great Depression. The 2018 total even edged out the losses under George W. Bush in 2006, which was the last time the Democrats re-took the House in a midterm election.

"This one was clearly pretty bad," said Alan Abramowitz, an Emory University political scientist.